Machine for mining



f Jan. 2, 1923. 1l,44,789

E. C. MORGAN. MACHINE FOR MINING4 FILED DEC. 3. 1915. 13 SHEETS-SHEET 2 777%071 Zar.' I 0 Z474 55; jaw 2171?@ /Vazyn `Fam. 2, E923.

E. C. MORGAN MAcHlNE FOR MrNlNG. Fl LED Dsc. 3

13 SHEETS-SHEET 4 www md, fr a M m.. HM,

Jan. Z, 1923.

13 SHEETS-SHEET 6 E. C. MORGAN. MACHINE FoR Mmm@ Fl LED DEc. 3. l 915.

FILED Dsc. 3, 1915. I 13 smears-SHEET 7 Jam, 2, i923.

Jam 2, l923 31,4%@9789 E. CI- MORGAN. MAcHmE FOR Mmms. FILED Dsc. 3, 1915. I3 SHEETS-SHEET 8 HHHI Il ifi-11653. 3y y 2 0%@ JM j# Jana, 29 E923. LLMUS@ E. C. MORGAN. MAcHlNE FoR MINING. FxLED DEc. 3. 1915.

I3 SHEETS-SHEET 9 Jam 2, N230 I3 sHEETs-sHEET 10 E. C. MORGAN. MACHINE FOR Ml NIN@ Fl LED DEC. 3, 1915 @www NNN SS@ QN M 91 ss Jan. 2, 1923. 1,440,789 E. C. MOIVIGAN. MACHINE FOR mms FILED Dec. 3. 1915 1v3 sHeaTs-sHesr 1 1 Wifi/(65S, I 'y/ l y 72751@ M E. C.w MORGAN. MACHINE PoR MINING FILED Dsc jan. 29 H923 I3 SHEETS-SHEET l2 n fge??? Zoff JJ??? whiff/Vary@ Patented Jan. Z, 1923.

UNET FTS' EDMUND C. MORGAN, OF CHICAGO, ILLINOIS.

MACHINE FOR MINING.

Application filed December 3, 1915. Serial No. 64,905.

To all whom it may concern:

Be it known that I, EDMUND C. MORGAN, a citizen of the United States, residing in Chcago, county of Cook, and State of Illinois, have invented a certain new and useful Machine for Mining, of which the following is a specification.

The invention relates to mining machines of the core cutting type, and one of its objects is the provision of a simple and eiiicient core cutting mechanism combined with dislodging mechanism and conveyer apparatus in amining and loading machine. Other objects of the invention will appear hereinafter, the novel features, and combinations of elements, being set forth in the appended claims.

In the drawings- Fig 1 is a side elevation of the rear portion, and Fig. 2 of the front portion, of the machine forming a part of the present invention; Fig. 3 vis a top plan view of the rear portion and Fig. 4 of the front portion of the machine shown in Figs. 1 and 2; Fig. 5 is a longitudinal section of the rear portion and Fig. 6 is a longitudinal section of the front portion of the machine shown in the figures described above; Fig. 7 is a cross section on line 7-7 of Fig. Fig. 8 is a fragmentary plan view of a portion of a conveyer belt used in this invention; Fig. 9 is a. fragmentary front elevation of the forward portion of the machine showing certain parts folded; Fig. 10 is a rear elevation of a fragmentary portion of the frame of the machine, showing one of the motors and associated parts; Fig. 11 is a fragmentary side elevation of a portion of the truck of the machine showing the mechanism for raising and lowering the operating head; Fig. 12 is a fragmentary sectional view looking down on a central portion ofthe machine and showing the joint between the relatively movable parts of the frame; Fig. 13 is a fragmentary horizontal sectional view showing one of the motors and associated gearing for driving various parts of the machine; Fig. 14 is a central vertical sectional view of the operating head used on the mining machine; Fig.

15 is a transverse vertical sectional view of the head shown in Fig. 14: Fig. 16 is a vertical sectional view substantially on line 16-16 of Fig. 15; Fig. 17 is a detail view showing the arrangement of certain of the gears used in the operating head; Fig. 18 is a horizontal sectional view on line 18-18 of Fig. 15; Fig. 19 is a top plan View of the operating head of the machine with the top cover removed; Fig. 2() is a sectional detail of a shaft coupling used in one of the drive shafts of the machine; Fig. 21 is a diagrammatic plan View of a portion of a mine chamber, illustrating a method of mining which can be carried out by the use of the present invention; Fig. 22 is a vertical longitudinal sectional view of the mine chamber shown in Fig. 21; Fig. 23 is a l0n gitudinal vertical sectional view of a mine chamber illustrating one of the steps in the process of mining comprising part of the present invention; Fig. 24 is a transverse sectional view of a mine chamber formed during the process of mining comprised in this invention; Fig. 25 is a diagrammatic top plan view; and Fig. 26 is a diagrammatic vertical longitudinal section of a. mine. chamber illustrating steps in the process of this invention.

In order that this invention may be best understood, the machine by which the process is carried out, will first be described, and the method will then be more clearly understood. Referring first more particularly to Figs. 1 to 7, inclusive, and Figs. 1() and 11, the numeral 1 designates generally the elongated machine frame having longitudinally extending side plates 2 mounted on wheels 4 and 5 of a truck on which the machine is carried. The side plates 2 of the frame 1 are secured together at their lower edges b v a box-shaped casting 6. (Figs. 5 and 7). which extends transversely of the machine from one side to the other and longitudinallj7 of the machine forwardly from the rear end to a point short distance back of the rear wheels 4. The side plates 2 are secured to the member (i by means of cap screws or other suitable fastenings 7, and the plates 2 are provided with inwardly extending ribs 8 to cooperate with theupper edges of the member 6 to assist in forming a rigid frame structure. As best shown in Fig. 3 of the drawings, the side plates 2 of the frame 1 are offset at 9 at a point near the rear wheels ofthe truck to provide a wider space between the forward portions of said side plates than that between the rear portions thereof. As shown in Figs.

'1 and 11, the side plates 2 are provided at their lower edges near the offset portion 9 with journal bearings 10 in which the axle 11 which carries the forward wheels 4 1s mounted.

The wheels 5 are carried by a transverse rod 12 connecting the extreme forward portions of the side plates 2. The side plates 2, with the transversely extending connecting member 6 and the wheels 4` auxiliary frame 13 comprises side plates 15 connected at their bottom by a pair of webs or plates 16 and 17. Both plates 15, as shown in Figs. 5 and 13, have rearwardly and downwardly extending bearing lugs 18 journalled for pivotal movement on the shaft 14, and in openings in the side plates 2 of the main frame concentric with the shaft 14. The connecting webs 16 and 17 of the auxiliary frame 13 extend forwardly to a point slightly in the rear of the operating head. From this point the bottom portion of the auxiliary-frame is continued forwardly by a heavier plate or floor member 20, as best shown in Fig. 6, on which member the operating portions of the mining machine head are mounted in a way to be described.

As will be seen from Figs. 1, 5 and 13, the side members 2 of the main frame 1 have downwardly extending portions 21 located in the rear of the ltruck wheels 4 and arranged to carry operating mechanism for 'various parts of the machine. A supporting plate 22 connects the lofwer portions of these members and is secured to them by means of bolts 23 as shown in Fig. 11. ounted on and supported by the plate 22 is a motor 24 as shown in Fig. 10. The motor 24 is arranged to drive the pinion 25 (Fig. 13), meshing with the gear 26, which is coaxial with and drives the pinion 27. The pinion 27 meshes with the gear 28 secured to the shaft 29 on which the drum 30 is loosely mounted and to which it may be clutched by means of the clutch 31. A cable 32 may be wound on the drum 30 for positioning the machine in the mine chamber or for moving sections of the trackwhen occasion requires.

A second gear 33 meshes with the pinion 27- and is rigid with and drives the shaft 34. A sprocket wheel 35 is loosely mounted on the shaft 34 and may be secured thereto by the clutch 36. A sprocket chain 37 (Fig. 5) operatively connects the sprocket 34 with a second sprocket wheel 38 rigidly secured to.

the axle 11 on which the wheels 4 are mount- By this construction the minin'gmachine'may b ehmoved along the track 40 'to properly positionhit in ,the mine chamber.

The direction of motion is controlled by reversing the motor 24.

Loosely mounted on the shaft 34 and arranged to be clutched thereto, is a gear 42, (Fig. 13) which meshes with a gear 43 rigidly secured to the shaft 14 which has also rigidly secured thereto the sprocket Wheels 45. At opposite ends of the shaft 14 and rotatively mounted thereon are two gears 46 and 47 respectively. The gear 46 is carried by a hub 48 journalled for rotation in the lug 18 of the pivoted frame 13. The hub 48 forms a bearing in which the shaft 14 is j ournalled. A bevelled pinion 49 is keyed to the hub 48 for rotation therewith and meshes with a second bevelled pinion 50 (Figs. l and 3). The bevelled pinion 50 is carried by a shaft 51 which is journalled in a bracket 52 whichbracket in turn is journalled on the end of the hub 48. This arrangement permits a pivotal movement of the shaft 51 about the axis of the shaft 14 without disturbing the driving engagement of the pinions 49 and 50. The gear 46 meshes with a gear`52 rigidly'rnounted on the shaft 34. By this connection the bevelled pinions 49 and 50 and the shaft 51 are rotated whenever the motor 24 is driven.

The gear 47 at the end of the shaft 14 opposite the pinion 49', is rigidly carried on a hollow hub or sleeve 53 in which the end of the shaft 14 is journalled, and which has rigidly secured thereto the gear 54.y The sleeve or hub 53 is journalled for rotation in the pivotal lug 18 of the frame 13. The gear 54 meshes with a gear 55 loosely mounted on the shaft 34 to which it may be secured by a double clutch 56. The clutch 56 is also used for clutching the gear 42 to the shaft 34 and `is operated by a handle 57 carried on a rod extending to the outer side of the machine, as shown in Fig. 1. Similar handles 58 and 59 are provided for operating the clutches 36 and 31 respectively.

In order to make two cuts for each position of the machine, one cut above the other, the auxiliary fra-me 13 is arranged to be tilted about the shaft 14 as an axis. To accomplish this tilting. the rack 60, (Fig. 11) is secured to one of the side plates 15 of the frame 13 at a point adjacent the forward end of the side member 2 of the main frame 1. A .pinion 61 is mounted on an upstanding lug' 62, secured to the forward end of the side plate 2. The pinion 61 is carried by one end of a shaft 63, the other end of which carries a worm gear 64. The gear 64 meshes with a worm 65 carried by the forward end of the shaft 66. The rear end of the shaft 66 (Figs. 3 and 11) is journalled in a bracket 67 secured to the side plate 2. A bevel gear 68 is carried on the end of the shaft 66 in position to mesh with the gear 47 carried as shown in Fig. 13 on the axis of the shaft 14. By this arrangement, when the clutch 56 is this arrangement the operating head of thel machine may be raised or lowered into posiion to make the different cuts illustrated in .A shaft 70 (Figs. 1, 3 and 5) extends from one side of the main frame 1 to the other at a pomt adjacent the truck wheels 4, and carries a pair of cams 71 arranged .to cooperate with brake shoes 72 pivotally suspended from the sides 2 of the frame 1 in `position to bear against the wheels 4. A 4llorake leverv73 is carried at one end of the shaft 70 and is arranged to cooperate y,with the ratchet bar 74 to hold the brake in position when setto lock the wheels 4.

Referring to' Figs. 3 to 8 inclusive, it will beseen that a conveyer belt 75 extends longitudinally of the machine throughout the grea'ter portion. of the length thereof along the chutes formed by the main and supplemental elongated frames. This belt passes over a roller 76 at the rear end o f the main frame and over a roller 77', near the forward end of the auxiliary frame. The upper run of the belt is supported by the upper web or platform 78 of the base member 6 of the main frame 1, and by the upper web or inclined platform 16 of the auxiliary' frame 13. The lower run ofthe belt is supported bythe lower' web or horizontal platform 7 9 of the main frame 1 and by the lower web or inclined platform 17 of the auxiliary frame 13. The belt itself,

as shown in Fig. 8 is made up of narrow strips 8() ofl sheet metal -secured together at their edges by hinged connections 81. Each of the :hinged connections 81 carries at the edge (if the belt a lug 82, and these lugs are arranged to cooperate with the sprocket wheels 45 carried by the shaft 14,

by means of which the belt is driven. As shown in Fig. v5, theA lower supporting plates 79 and 17 terminate a s hort distance from one another near the pivotal support of the frame 13 in order to provide space Vfor the cooperation .of the sprocket wheels 45 with the chain 75. Inorder that there may be no break in the support for the upper run Y. of the belt, the'web 1'6 of the pivoted frame l-S is provided with tongues 83 which pro-Y ject rearwardly and cooperate with registering slots 84 cut in the forward end of the web 7 8. This construction is best shown in Fig. 12. When the auxiliary frame113 is moved on its pivot, the tongues 83 and slots 84 will move relative t0 `one another, but the space between the webs 16 and' 78 will always be bridged by the tongues-83,

thus forming a continuous support for the conveyer chain. The movement of theconveyer chain, as previously explained, is controlled by means of the clutch 56. Overhanging guide flanges 85 extending toward each other from the plates 2 as shown in Fig. 7 are provided throughout the entire length of the conveyer and extend over the edges thereof to guide the conveyer and hold it in proper position.

It should be noted that the elongated main frame comprising the spaced-apart side plates 2 `and the connecting platform 78 in reality constitutes an open-ended chute for guiding the coal carried rearwardly by the endless conveyer mechanism. It should also benoted that the supplemental frame comprising` the upright spaced-apart plates 15 and the connecting inclined platform 16 constitutes a chute which may be inclined downwardly or upwardly or held in a substantially horizontal position while being in alinement with the rear chute which is adapted to overhang a mine car, as shown in Figs. 1, 5 and 22. The forward elongated chute is also ope-nended and its rear end telescopes into the forward end of the main frame or rear chute. As shown in Fig. 18 the Vsupplemental frame 13 which carries the spacedapart upright' plates 15, is journaled in bearings in `the spaced-apart plates 2 for tilting up and down movement on the axis of the shaft 14. The supplemental vframe is therefore confined against lateral movement relatively to the main framewhich enables the use ofthe single endless condriving the endless conveyer is not inter! fered with by the tilting of the. supplemental frame relatively t0 the main frame. By locating the driving mechanism for the conveyer on the axis of the pivot for the forward supplemental frame, such driving mechanism. as shown in Fig. will maintain the conveyer taut along that portion which extends below' the platform 78. The lower platform 79 may therefore in some instances be omitted but l prefer to use it in such instances where the loading of mine cars, as shownin Fig. 22, might cause the tilting of the forward end ,of the car up against the conveyer. The lower inclined platform 17 is preferably employed to protect the conveyer when it tends to.become Vslackland to hang down too low. The tuother, as shown in Fig. 5, with their connecting ends registering where the driving mechanism is located. It will thus be seen .are maintained in alinement with each other so as not to interfere with the free travel of the endless conveyer.

The coal is severed from the inner upright ywall of the mine chamber by core-cutting apparatus carried on the base plate or platform 2O secured to the forward end of the tilting or auxiliary frame 13. Referring to Figs. 14 and 15, it will be seen that the platform 20 is provided with a centrally located lbearing lug 86. Mounted on the bearing 86 for rotation about a vertical axis. is a circular shell or skeleton frame 87 which is provided with four inwardly projecting' lugs 88 which support an electric motor 89 within the frame. The shell 87 is provided with a circular journal 90 which surrounds the bearing portion of the lug 86 and which is held in place by a stationary gear 91 which is rigidly secured to the upper surface of the bearing lug 86 by anumber of cap screws 92. The armature shaft of the motor 89 is provided with a pinion 93 which meshes with a gear 94 rotatably mounted on a stud shaft secured to the lower portion of tht` casing of the motor 89. Rigidly'secured to the gear 94 for rotation therewith are a spurA pinion 95 and a bevelled pinion 96` shown best in Fig. 15. The spur pinion 95 meshes with two gears 97 and 98 (Fig. 17), rigidly mounted on shafts 99 and 100 respectively. Referring to Fig. 18 it will be seen that the shaft 99 which carries the gear 97 has a worm 101 journalled for free rotation thereon. This worm 101 may be secured to the shaft 99 for rotation therewith by means of the clutch 102. The clutch 102 is operated by a rod 103 which extends upwardly to the top of the casing and is provided with a handle 104 (Fig. 4).by means of which it is operated. rl`he worm 101 meshes with a worm wheel 105 (Figs. 14 and 18) rigidly secured to an upright shaft 106 which carries a spur pinion 107 in position to mesh with the stationary gear 91 secured to the platform 20 by the screws 92. Bv this arrangement. the motor 89 may be clutched toA the train of gearing described, and the pinion 107 be thus caused to travel around the gear 91 and carryi the entire skeleton 113 is carried by lugs 114 which project inwardly from the walls of the casing 87. Extending horizontally from the lower portion of the frame 87 at a point adjacent the sprocket wheel 112, is the lower bar 115 of a loop chain core cutter 116. A chain 117 of this cutter is guided along the front portion of the bar 115 and passes over the sprocket wheel 112 by means of which it is driven. The frame of the core cutter 116 in addition to the lower horizontal bar 115 has an upwardly extending portion 118 and an upper horizontal bar 119 (Fig. 6) which extends inwardl and is secured to the upper portion of the rame 87 (Fig. 14) and held thereon by an upwardly extending arm 120. The arm 120 is rigidly mounted on a cover plate 121 which tits over the top of the frame 87 and is secured thereto by bolts 122 (Fig. 4). Guides 123 and 124 are provided for directing the chain 117 over the sprocket wheel 112 in the cutter head frame.

Surrounding the skeleton frame 87 and arranged to rotate relative theretois a hollow cylindrical casing 125. The 'shell 125 is supported by a flange 126 extending outwardly around the bottom edge of the frame 87. The upper edge of this shell is provided with inwardly projecting gea-r teeth 127 (Figs. 13 and 19) by means of which the shell is rotated relative to the skeleton frame. The teeth 127 mesh with a pinion 128 carried on a vertical shaft 129 journalled in lugs 130 and 131 carried by the frame 87, as best shown in Figs. 15 and 16. Mounted for free rotation on the shaft 129, is a pinion 132 meshing with the pinion 96 driven by the motor 89, as previously described. The pinion 132 ma be secured to the shaft 129 for rotation tierewith by the clutch 133, which is slidable on the shaft 129 by means lof a lever 134 and a connecting link 135. By

this mechanism the pinion 128 may be driven by the motor 89 and thus cause the shell or sleeve 125 to rotate about the skeleton frame 87. Rigidly secured to the hollow cylinder 125 and extending laterally therefrom, are a pair of superposed arms 136 (Fig. 14) which carry a vertical Wing or plate 137 which is of a size to pass freely through the unobstructed core-opening of the loop chain core-cutter 116 but large enough to substantally lill the space surrounded by the cutter loop. A stop 138 (Fig. 4) is provided in the path of the movement of the plate 137 to limit the rotation of this plate inv one-diy rection. It will be seen from the drawings an'd description of the motor 89 and its as.- sociated parts, that the cutter frame' and the chain 117 may be simultaneously driven by the motor to form a kerf in the material to be mined, for the purpose of severing the material from the mine Wall. It will also be seen that the frame 87 which carries the cutter frame 116 will be'rigidly held in whatever position it is moved into by the worm drive by means of which it is operated. Because of this fact, the plate 137 carried by the hollow cylinder 125 may be rotated about the frame 87 tdremove the severed-material in a manner to be described.

For the purpose of reducing the friction between the severed material and the wall of the mine, and for properly guiding this material into position from which it may be transported, a exible apron 139 'is provided one end of which is, as shown in Fig. 4, secured to the rear portion of the upright cutter bar 118 of the cutter frame. This apron is somewhat similar in construction to the conveyer belt 7 5, being made up of metal strips hinged together at their edges; but the apron differs from the conveyer belt in that the inner surface of the apron is made as smoothas `possible in order to permit the mined material to slide freelyl against the inner surface thereof. The rear end of the apron is secured to a reel 140 (Figs. 2 and 4) on which the apron may be wound. The reel 140 is driven by a screw 141 carried byy a shaft 142 which is operatively cohnected with the shaft 51 by a. universal coupling 143. The worm 141 may be clutched to the shaft 142 for rotation therewith by means of a clutch 144 operated by a lever 145 mounted on the opposite side of the machine and connected with the clutch by means of a rod 146 and bell crank 147 (Fig. 4). By means of this worm drive the reel 14() is rigidly held from rotation except whenv positively driven by the motor 89 through the shaft 51. The direction of 'rotation of the reel 14() depends on the direction of rotation of the driving motor. The motor 89 is operated through a controller 148 mounted on a guard wall 149 projecting upwardly from the base plate 20. A second controller 150 is also carried by the guard wall 149 and is connected to the motor .'89 in the casing 87 of the machine by cables 151 (Fig. 14). Current is supplied tothe motors by means of a trolley line in a manner well known in the art. n

'lhe .shaft 51 is provided with a friction or slip coupling 152 (Fig. 2) the construction of which is best shown in Fig. 20. The two ends of the shaft 51 are disconnected from one another and are provided with' I' shaft.

Ath'e machine is in operation.

slide longitudinally on the shaft and is forced toward the member 154 by means of The friction member 153 is free toa coil spring 155, thus providing constant frictional contact between the two members 153 and 154. So long as the torsion between the two sections ofthe shaft 51 does not eX- ceed a certain limit, the sections will continue to rotate in unison. the torsion becomes great enough to overcome the friction between the members 153 and 154, the sections will rotate relative to one another. The two sections are provided with surrounding casing members 156 and 157 respectively for enclosing the operating parts of the friction coupling.

In order that the platform 20 may extend the full width of the mine chamber and yet be folded to a width corresponding to that of the machine when the machine is being transported from one chamber to another,

When, however, A

the plate 2O is provided at each sidewith Y hinged extensions 160 (Fig. 4). These eX- tensions, as shown in Fig. 9, may be folded up against the cutter head when .the machine is being transported, and may be extended, as shown in broken lines in Fig. 9, when One of the extensions 160 is provided with -a stop 161 against which a pivoted guard 162 (Fig. 4) is swung and by means of which the outward movement of the guard is limited (Fig. 2). The guard 162 is pivoted at 163 and .may be swung inwardly to a position over the main portion of the platform 20 in front of the conveyor 75 when the extensions are folded for transportation. Before the parts of the platform are folded as described, the cutter frame 116 and the-arms 136 and plate 137 are swung about the-ir pivot until they occupy a position in the rear of the cutter head. In this wayall of the partsof the cutting and loading apparatus may be brought into compact relation to one an- Aother when the machine is being transported.

The operation of the disclosed embodiment of the invention is'as follows:

The machine is located ina mine chamber,

as shown in Figs. 1 to 6 inclusive, and thev auxiliary frame is tilted to its uppermost position, that is into the position for making a cut at the upper portion of an upright wall in 'the mineI chamber. The o-perator iio will then start the motor 89 in the cutter l head and connect the sprocket wheel 112 by means of the clutch lever 110 (Figs. 2, 4

107 which begins its travel about the gearv 91 carrying the cutter frameI with it about the bearing lug 86 as an axis. In this way a U-shaped kerf is formed in the materia-l to he mined, which severs a portion of the material crescent-shaped in horizontal section,

as shown in Fig'. 4. During the forward movement of the cutter 116, the motor 24 may be operated to drive the reel 140 to permit the apron 139 to be paid out and drawn into the kerf formed by the vertical portion of the. cutter 116. If at any time it is found desirable to break awa-ythe portion of the material severed, this may be done by throwing out the clutch 144 and stopping the movement of the reel 140, thus holding the end of the vapron stationary. If this is done while the cutter continues to rotate, the apron will be drawn tighter and will bring pressure to bear on the severed surface of the material, thus causing portions of it to be broken olf. The same effect may be produced by stopping the feed of the cutter 116 and driving the reel 140 in the direction to Wind up a portion of the apron 139. Whether such breaking operation will be necessary or not, will depend upon the nature of the material being mined. In many places in coal mining the coal will break up sufficiently of its own accord without any positive breaking operations. After the cutter frame 116 has rotated a sufficient amount to completely sever the section of material, the movement of the cutter will be stopped and the frame will then be rigidly held from rotation by the worm gear by means of which it is driven. When the material has thus been completely severed, the lever 134 (Fig. 16) is moved by the operator to cause rotation of the pinion 138 to drive the hol- 35.low cylindrical casing 125 (Fig. 19) rotating it about the axis of the cutter head in a direction opposite to the cutting direction of the cutting frame. This movement of the hollow'cylinder 125 carries with it the arms 136 and the. plate 137 which thus form a mover or follower for the severed material which forces the material before it in the reverse direction of the movement of the cutter and carries the dislodged material before it backwardly onto ,the supporting base plate or platform 20. During this movement the apron 139 prevents frictional contact of the severed material with the mine wall and thus permits the material to be slid freely before the plate 137 and onto the receiving platform 20. As the material moves backwardly, it is guided by the guards 149 and 162 or along a chute comprising such guards into a position adjacent the forward end of the conveyer 75. In the meantime the conveyer is being driven by the motor 24 and connected mechanism (Fig. 5), and

as fast as the material is forced upon the end of the conveyer,it is taken up and carried rearwardly along the bod of the machine to the rear end thereof w ere it is discharged into a car or other conveying mechanism from the rearwardly extending main frame which is adaptedto overhang a mine car, After the completion of each'cut and the removal of the severed material, the loop core cutter is returned to its initial position and the apron 139 simultaneously rewound upon4 its reel. The slip or friction drive `152 is provided in the shaft 51 to compensate for any inequality in the rate of motion of the drives for the two ends of the apron. After the upper cut has thus been completed, the. tilting frame is swung downwardly and a second cut is made just below that made by the machine whileI in its upper position (Fig. 2). )Vhen both these cuts have been made, the chamber will then extend into the walls of the mine a distance equal to the depth of the cuts made. The machine is now moved forwardly in the chamber and the operation is repeated.

The novel features of the method of min ing employed in connection with the machine thus described will be best understood by referenceA to Figs. 21 to 26 inclusive. In Figs. 21 and 22 the machine forming part of this invention is designated by the numeral 200 and is diagrammatically shown in position in a mine chamber. In Fig. 21 the shape of the various cuts made by the machine as viewed from above is illustrated by the pcrescent-shaped figures 201. These figures'are formed by successively removing sections of the material from its native bed by the rotation of a loop core cutter in a horizontal direction about an upright axis. and by forcing the material thus removed from the position it occupied in its native bed by a follower which swings about the same axis as the loop core cutter' and which moves the material rearwardly onto a conveyer which 'carries it to a position where it may be transported from the mine. The chamber formed by the machine is, however, of a greater height than can be produced by a single out, and in order to form a. chamber of a sufficient height, two cuts are made one above the other for each position of advance of the machine into the chamber. The portion of the machine which carries the mechanism for forming these cuts is movable about a horizontal pivot to position the cutter inits upper and lower positions. The outline of the different cuts formed by the machine as viewed in vertical section, is designated by the numeral 202, Fig. 22. It frequently happens in coal mines that a stratum of undesirable material is found in a mine bed. Such a stratum is shown in the figures referred to and is designated by the numeral 203. In the present process of min ing, this stratum 203 is first removed by a machine arranged to form a horizontal kerf in the material to be mined. Such machines are well known in the art and one such machine is diagrammatically shown in Fig. 23 and designated by the numeral 204. In carrying out the present method, the stratum of undesirable material is first removed cuts to be made by the mining machine proper before the entire material from which the undesirable stratum has been removed is completely mined. Fig. 25 shows in plan view a portion of a mine chamber from which the stratum of undesirable material has been removed for a sufficient distance to permit several cuts to be made by the mining machine. 'In this figure the numeral 201 designates two cuts already made by the machine, and the numeral 205 designates the portion from which the stratum of undesirgablelnaterial has been removed. Fig.'26 designates in vertical section the lines of cleavage shown at 206, and the sections of detached material shown at 207 formed during the mining process. v The opening 208 indicates a portion from which .the stratum of undesirabley material .has been removed. Fig. 24 is a transverse sectional view of the mine chamber formed in carrying out the present process. It should be noted that the upper part of the chamber is arched transversely thereof. This is due to the fact that while the uppermost cut is being made the portion of the frame carrying the loop core cutter is tilted upwardly to such a position that the axis of rotation of the cutter is inclined backwardly from the vertical. This causes the forward portion of the cutter to reach its highest position when it is at the center of its travel while making a cut transversely of the mine chamber. The floor of the mine chamber is also curved but to a much lessdegree than the roof of the chamber, due to the fact that the pivot about which the supporting frame for the operating head is tilted, is much nearer the ioor of the mine than it is the roof. This arching of the mine roof is very important, as it forms a support for the roof, and enables the chamber to be cut without the use of props. It will be noted by referring to Figs. 22, 23 and 24, that a stratum of material 209 is shown above the layer of coal being mined. This is the. usual condition in which coal is found', material 209 often being slate. It has been found that if all of the coal i's removed from beneath a layer s of slate, the action of the air upon the slate will soon cause it to break and fall into the mine chamber. In-the present method of mining, a thin layer of unmined coal is left below the Ystratum of slate, as shown at 210 in Fig. 24. .This layer of coal at the center of the arch formed by the machine, is only of sutiic'ient' thickness to prevent the deteriorating action of the atmosphere upon the slate located above the coal. The layer of coal, of course, is thicker at the sides of the chamber in order to form the supporting arch. 'In this way, a self-supporting charnber having an arch-shaped roof which remains intact for a long period of time, is produced. The two machines used to perform the different steps in the mining process are mounted on their trucks forthe purpose of facilitating the interchange of the machines in the mine chamber after the completion of the steps performed by each machine and also to provide easy transportation of the machines from one chamber to another.

I claim:

l. In a mining machine, the combination with a truck frame having a rearward extension adapted to overhang a mine car on a mine track on which saidrtruck frame is mounted, of a supporting frame pivotally mounted on said truckframe on a transverse axis for up and down swinging movements from positions at t-he floor of the mine chamber to positions at. the roof thereof along an upright mine wall, kerf cutting mechanism mounted on the forward end of said supporting frame for swinging feeding movements on an upright axis, means for operating said kerf cutting mechanism including swinging feeding movements thereof on such upright axis, and self-acting power mechanism connected betwfeen said truck frame and said supporting frame for tilting the latter on its pivotal connection to said truck frame to effect adjustment in elevation of said kerf cutting mechanism.

2. In a mining machine, the combination with a truck, of a supporting frame pivotally mounted on said truck to extend forwardly in advance thereof, kerf cutting mechanism mounted on the forward end of said supporting frame for swinging feeding movement relatively thereto on an upright axis in position for operation on an upright mine wall in advance of said frame, an upright arcuate rack on said supporting frame intermediate its forward end and its pivotal connection to said truck, and self-acting power mechanism connected to said aipright arcuate ,rack for tilting said supporting frame up downl on said truck to adjust the elevation of said kerf cutting mechanism.

3. In a mining machine, the combination with a truck having a main frame, of an auxiliary frame pivot-ally connected to said main, frame for up and down movement rel- 'atively thereto. on a substantially horizontal llO 

